Of course, genetics play a role and those with a family history are at increased risk, but there are things anyone can do to reduce the risk, she explains.

These include paying attention to cardiovascular risk factors such as cholesterol and high blood pressure and keeping diabetes under control. Treatment of these medical problems helps prevent vascular disease in the brain that can cause cognitive problems.

In addition, several studies suggest that by preventing vascular disease, you can help people with Alzheimer’s disease. “This is because it will take more of those plaques and tangles that are found in the brains of people with Alzheimer’s disease to develop symptoms of dementia,” she says.

Dr. Kandel also suggests protecting the head by wearing a helmet while bicycling, for example, and always using seat belts.

“But if you have memory problems it is not always Alzheimer’s disease,” she adds.

Sometimes, memory issues are the result of depression, medications or a vitamin deficiency, she adds. Sleep problems can also contribute to memory loss.

She recommends older people take more time in accomplishing tasks and not try to multi-task.

To keep the memory sharp, she recommends doing mental exercises, such as playing crossword puzzles, and staying active and socially involved. Exercise also helps.

“Try something new,” she says. “Learn to play the piano.”

Irving Silverman, 93, of Dedham, says he takes pains to stay sharp.

“I participate in as many activities as I can,” he says. “I’m a very social person and I like to be around people who are positive.”

Silverman, twice widowed, says he plays scrabble and other word games and follows politics closely.

“I’m a political junkie,” he says.

He once had a benign tumor removed from his brain and lost a lot of memory function but worked hard to get it back with occupational and speech therapy.

“I have an optimistic view of tomorrow,” he says. “I want to live to be 120.”

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